1) API Spec 5CT. 2) J55, K55, N80, L80, P110 3) NUE&EUE API 5CT N80 TUBINGStandard: API 5CTSize: 2 3/8", 2 7/8", 3 1/2", 4", 4 1/2"Steel grade: J55Type: NUE, EUELength: R1, R2, R3 N80 Physical PropertiesY.S. : 552Mpa~758MpaT.S. Min : 689Mpa API 5CT N80 seamless steel tubing